Defining relational and object-oriented databases
A relational database system comprises of a collection of data tables which are organized according to a specific relational model. The data present in a single table has a relation, which is the reason behind naming this type of database system.
On the other hand Object-Oriented database systems have the information represented in the form of objects similar as the case of object oriented programming. A new database system known as object-relational database had been developed, which is a combination of both these concepts.
Relational Databases - The main advantage of relational database systems is that data gets stored only once and allow to complicated queries. The system is also flexible for future requirements because the data gets stored in different tables, allowing easier addition of new records.
Object-Oriented Databases - One of the major advantages of object oriented database systems (OODB) is that it requires reduced maintenance. The system has a relatively longer life cycle and the maintenance costs are far lower. Most of the processes are encapsulated, making it possible to reuse the behaviors and incorporate them into new ones, also known as inheritance.
Another advantage of OODBs is that they represent real-world modeling at a higher level compared to other conventional systems. The objects are arranged into different classes of objects and they are related by behaviors. The overall model is based on objects and not on data or processing.
The next advantage of using OODBs is that they are highly flexible and reliable. This system is more reliable compared to conventional systems and one of the main reasons is that it is possible to create new behaviors from existing objects. It is possible to call or access objects dynamically, making it easier to create new objects any time. These new objects could take data features from one or more objects. It is possible that the behaviors can be taken from super classes and the novel behaviors can be added without any effect on the current systems functions.
Another advantage of using object-oriented databases is their high level of code reusability. If a new object gets created, it is going to automatically get the data features of the class from which it was produced. It will also receive the data and behaviors of all the superclasses where it participates.
Relational Database Systems – The latest open-source and commercial databases are relational. The most popular open-source and proprietary applications include SQL Server, Oracle DB, Postgres and MySQL.
Object Oriented Databases – OODBs have a niche application area in engineering, scientific fields and telecommunications. Molecular biology and high energy physics have seen widespread use of these types of databases.